Reduced-pressure dressing assemblies for use in applying a closing force

ABSTRACT

A closing dressing bolster and assembly for use with a system for treating a linear wound on a patient includes a bolster body formed from a flexible closing bolster material having closing members that are operable to develop an inward closing force when the closing dressing bolster is placed under reduced pressure. In one aspect, when the closing dressing bolster is under reduced pressure, the system, dressing, or assembly develops an inward force realized at the linear wound and a compression force. A wicking-material holder and wicking material may be used as well. The member components may all be see-through to allow visual inspection of the wound without requiring removal of the dressing.

RELATED APPLICATIONS

This Application is a Divisional of U.S. Non-Provisional patentapplication Ser. No. 12/475,328, filed May 29, 2009, which claims thebenefit, under 35 USC §119(e), of the filing of U.S. Provisional PatentApplication Ser. No. 61/057,807, entitled “Reduced-pressure SurgicalWound Treatment System,” filed May 30, 2008; U.S. Provisional PatentApplication Ser. No. 61/057,798, entitled “Dressing Assembly ForSubcutaneous Wound treatment Using Reduce Pressure,” filed May 30, 2008;U.S. Provisional Patent Application Ser. No. 61/057,808, entitled“See-Through, Reduced-Pressure Dressing,” filed May 30, 2008; U.S.Provisional Patent Application Ser. No. 61/057,802, entitled“Reduced-Pressure Dressing Assembly For Use in Applying a ClosingForce,” filed May 30, 2008; U.S. Provisional Patent Application Ser. No.61/057,803, entitled “Reduced-Pressure, Linear-Wound Treatment System,”filed May 30, 2008; U.S. Provisional Patent Application Ser. No.61/057,800, entitled “Reduced-Pressure, Compression System and Apparatusfor use on a Curved Body Part,” filed, May 30, 2008; U.S. ProvisionalPatent Application Ser. No. 61/057,797, entitled “Reduced-Pressure,Compression System and Apparatus for use on Breast Tissue,” filed May30, 2008; U.S. Provisional Patent Application Ser. No. 61/057,805,entitled “Super-Absorbent, Reduced-Pressure Wound Dressing and System,”filed May 30, 2008; U.S. Provisional Patent Application Ser. No.61/057,810, entitled “Reduced-Pressure, Compression System and Apparatusfor use on a Joint,” filed May 30, 2008; U.S. Provisional PatentApplication Ser. No. 61/121,362, entitled “Reduced-Pressure Woundtreatment System Employing an Anisotropic Drape,” filed Dec. 10, 2008;and U.S. Provisional Patent Application Ser. No. 61/144,067, entitled“Reduced-Pressure, Compression System and Apparatus for use on a Joint,”filed Jan. 12, 2009. All of these applications are incorporated hereinby reference for all purposes.

BACKGROUND

The present disclosure relates generally to medical treatment systems,and more particularly, but without limitation to, reduced-pressure woundtreatment systems suitable for use with linear wounds, such as surgicalwounds.

Physicians perform millions of surgical procedures each year around theworld. Many of the procedures are performed as open surgery and anincreasing number are performed using minimally invasive surgery, suchas arthroscopic, laparoscopic, and endoscopic procedures. As oneexample, the American Society for Aesthetic Plastic Surgery reports thatthere were more than 450,000 liposuction procedures in the United Statesin 2007.

Surgical procedures involve acute wounds, e.g., an incision or linearwound, in the skin and related tissue. In addition to surgical wounds,linear wounds are also caused by trauma. In many instances, the linearwound is closed using a mechanical apparatus, such as staples, suture,or adhesives, and then the wound is merely covered with a dry, sterilebandage. Often the bandage must be removed to view the wound to monitorhealing and to check for infection or other issues. Unless otherwiseindicated, as used herein, “or” does not require mutual exclusivity.

BRIEF SUMMARY

Shortcomings with aspects of linear wound care are addressed by thepresent disclosure as shown and described in a variety of illustrativeembodiments herein. “Linear wound” refers generally to a laceration orincision whether in a line or not. According to an illustrativeembodiment, a closing dressing bolster for use with a system fortreating a linear wound on a patient includes a bolster body formed froma flexible closing bolster material and having a center portion. Thebolster body includes a top wall and a bottom wall that are coupled in aspaced relationship. The bottom wall has a first lateral portion on oneside of the center portion and a second lateral portion on another sideof the center portion. A first closing member is formed on the firstlateral portion, and a second closing member is formed on the secondlateral portion. The first closing member and second closing member areoperable to develop a directed force when the closing dressing bolsteris placed under reduced pressure.

According to another illustrative embodiment, a closing dressing bolsterfor use with a system for treating a linear wound on a patient includesa bolster body formed from a flexible closing bolster material. Theclosing bolster body includes a first closing member formed on a secondsurface of the bolster body. The first closing member includes a firstoblique wall. The closing body includes a second closing member formedon the second surface of the bolster body. The second closing memberincludes a second oblique wall. The bolster body may further include awicking-material holder coupled to the bolster body and a wickingmaterial associated with the wicking bolster holder. The wickingmaterial has a fluid flow pathway for removing fluids. The first closingmember and second closing member are operable, when the closing dressingbolster is under reduced pressure, to develop an inward force.

According to another illustrative embodiment, a closing dressing bolsterfor use with a system for treating a linear wound on a patient includesa bolster body formed from a flexible closing bolster material, a firstclosing member, and a second closing member. The first closing member isformed on a second surface of the bolster body. The first closing memberis formed on a first lateral side of a center area. The second closingmember is formed on the second surface of the bolster body. The secondclosing member is formed on a second lateral side of a center area. Thefirst closing member and second closing member are operable to movetowards each other when placed under reduced pressure. The bolster bodyis operable to allow light to pass through sufficiently that color maybe detected from a location external to the closing dressing bolster.

According to another illustrative embodiment, a dressing assembly foruse with a system for treating a linear wound on a patient includes abolster body formed from a flexible closing bolster material. Thebolster body has a first surface and a second, tissue-facing surface.The bolster body includes a first closing member on a first lateral sideof a center wound area of the bolster body and a second closing memberon a second lateral side of the center wound area of the bolster body.The first closing member and second closing member are operable, whenthe closing dressing bolster is under reduced pressure, to move towardsone another and to develop a compressive force. The dressing assemblyalso includes an over-drape for disposing adjacent to the first surfaceof the bolster body and operable to form a seal over the bolster body.

According to another illustrative embodiment, a method of manufacturinga closing dressing bolster for use with a system for treating a linearwound on a patient includes the step of: forming a bolster body from aflexible closing bolster material. The step of forming the bolster bodyincludes the steps of forming the bolster body with a first lateral sideand a second lateral side. The bolster body includes a central area andthe first side is on one side of the central area and the second side onthe other side of the central area. The step of forming the bolster bodyfurther includes forming a first closing member on the bolster body onthe first lateral side of the central area and forming a second closingmember on the bolster body on the second lateral side of the centralarea. The first closing member and second closing member develop aninward closing force when the closing dressing bolster is placed underreduced pressure.

Other features and advantages of the illustrative embodiments willbecome apparent with reference to the drawings and detailed descriptionthat follow.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete understanding of the method and apparatus of the presentdisclosure may be obtained by reference to the following DetailedDescription when taken in conjunction with the accompanying Drawingswherein:

FIG. 1 is a schematic, perspective view, with a portion in crosssection, of an illustrative embodiment of a system for treating a linearwound on a patient;

FIG. 2 is a schematic, perspective view of an illustrative embodiment ofa closing dressing bolster for use in treating a linear wound on apatient;

FIG. 3A is a schematic cross-section of an illustrative embodiment of asystem for treating a linear wound on a patient;

FIG. 3B is a schematic cross-section of a detail from FIG. 3A;

FIG. 3C is a schematic cross-section of a detail from FIG. 3A;

FIG. 4A is a schematic, perspective view of an illustrative embodimentof a closing dressing bolster for use in treating a linear wound on apatient;

FIG. 4B is a partially exploded, perspective view of the closingdressing bolster of FIG. 4A showing one illustrative embodiment of atubing connector;

FIG. 4C is a cross-section of the closing dressing bolster of FIG. 4A;

FIG. 4D is a detail of the closing dressing bolster of FIG. 4C;

FIG. 5 is a schematic, perspective view of an illustrative embodiment ofa closing dressing bolster for use in treating a linear wound on apatient;

FIG. 6 is a schematic cross-section of a portion of an illustrativeembodiment of a system for treating a linear wound on a patient;

FIG. 7 is a schematic cross-section of an illustrative embodiment of aportion of a system for treating a linear wound on a patient; and

FIG. 8 is a schematic, perspective view, with a portion in crosssection, of an illustrative embodiment of a system for treating damagedsubcutaneous tissue that allows the wound to be seen from a pointexternal to the system.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

In the following detailed description of the preferred embodiments,reference is made to the accompanying drawings that form a part hereof,and in which is shown by way of illustration specific preferredembodiments in which the subject matter of this disclosure may bepracticed. These embodiments are described in sufficient detail toenable those skilled in the art to practice the disclosed subjectmatter, and it is understood that other embodiments may be utilized andthat logical structural, mechanical, electrical, and chemical changesmay be made without departing from the scope of this disclosure. Toavoid detail not necessary to enable those skilled in the art topractice the disclosed subject matter, the description may omit certaininformation known to those skilled in the art. The following detaileddescription is, therefore, not to be taken in a limiting sense, and thescope of the present disclosure is defined only by the appended claims.

Referring to FIGS. 1-3, an illustrative embodiment of a reduced-pressuresystem 10 for treating a linear wound 12, such as a laceration or, moretypically, an incision 14 is presented. The reduced-pressure system 10may hold or support peri-incisional tissue, enhance tensile strength ofthe incision 14; compress subcutaneous tissue 20; remove interstitialfluid, which may help reduce or eliminate edema; and isolate the linearwound 12 from infectious sources. The reduced-pressure system 10 may beparticularly well suited for use with at-risk patients, e.g., obesepatients, diabetic patients, smokers, etc.

While the linear wound 12 may extend to different depths, in this,example the incision 14 extends through epidermis 16, dermis 18, andinto the subcutaneous tissue 20. An damaged subcutaneous tissue 22includes, in this illustration, a subcutaneous void 24 or dead space.While not shown in this embodiment, the linear wound 12 may have anynumber of closing devices employed on the linear wound, e.g., mechanicalclosing devices (suture, staples, clamps, etc.), adhesives, bonding,etc. The wound may be or include a graft.

The reduced-pressure system 10 may include a dressing assembly 40, whichmay be placed over the linear wound 12 and used with reduced pressure tosupply a directed force, which may include a compressive force 42 or aclosing force 44 (or an inward force with respect to an outer edge ofthe dressing assembly). The dressing assembly 40 may include a closingdressing bolster 46 that under reduced pressure develops the directedforce, e.g., the compressive forces 42 or the closing forces 44. Theclosing dressing bolster 46 may be formed with a bolster body 50. Theclosing dressing bolster 46 is preferably made from a material thatallows flexing and yet is rigid enough to deliver a closing force.

The bolster body 50 may include a first closing member 52 and a secondclosing member 54. Additional closing members, such as members 56, 58,60, and 62 may be included. A sealing subsystem 70 and areduced-pressure subsystem 90 cooperate with the closing dressingbolster 46 to develop the directed force, e.g., the closing force 44 orthe compressive force 42.

The closing dressing bolster 46 may be made from a material that helpsto distribute reduced pressure to the linear wound 12, provides thecompressive force 42, and, through the closing members, e.g., closingmember 56, provides a closing force 44—preferably a force that issubstantially within the plane of the epidermis 16. In addition, thematerial for the closing dressing bolster 46 is preferably translucentor see through to an extent that light may pass through allowing one toview the linear wound 12 through the bolster material from a pointexternal to the reduced-pressure system 10. The material from which theclosing dressing bolster 46 may be formed is further described below.

As previously noted, the reduced-pressure system 10 may allow woundcolor, shades of color, wound edge, or other features to be perceivedvisually from a point external the reduced-pressure system 10. As such,the color, shades of color, nature of the wound edge, or other featuresmay be determined by a healthcare provider without requiring removal ofthe dressing assembly 40 and thereby may avoid the increased risk ofcomplications and pain of a dressing change. As such, the expense ofanother a dressing assembly 40 or part of thereof may also be avoided.The reduced-pressure system 10 may also provide the compressive force 42to the linear wound 12 and that force may help the linear wound 12,subcutaneous tissue 22, or subcutaneous void 24 to heal and maystabilize the linear wound 12 against shear. The reduced-pressure system10 may also help remove exudates from the linear wound 12 and may helpclose the void 24.

The sealing subsystem 70 may include the sealing member 72. The sealingmember 72 has a first side 74 and a second, inward-facing side 76. Aportion of the sealing member 72 may extend beyond the closing dressingbolster 46, e.g., beyond edge 48, to form a flap, or a drape extension77, which has a first side 78 and a second, inward-facing side 79. Thesealing member 72 may be any material that provides a fluid seal thatallows reduced pressure to be held. The sealing member may, for example,be an impermeable or semi-permeable, elastomeric material. “Elastomeric”means having the properties of an elastomer. It generally refers to apolymeric material that has rubber-like properties. More specifically,most elastomers have elongation rates greater than 100% and asignificant amount of resilience. The resilience of a material refers tothe material's ability to recover from an elastic deformation. Examplesof elastomers may include, but are not limited to, natural rubbers,polyisoprene, styrene butadiene rubber, chloroprene rubber,polybutadiene, nitrile rubber, butyl rubber, ethylene propylene rubber,ethylene propylene diene monomer, chlorosulfonated polyethylene,polysulfide rubber, polyurethane, EVA film, co-polyester, and silicones.Specific examples of sealing member materials include a silicone drape,3M Tegaderm® drape, acrylic drape (such as one available from AveryDennison), or an incise drape.

A sealing apparatus 80, or attachment device, may be used to helpprovide a fluid seal between the drape extension 77 and the patient'sepidermis 16. In the present embodiment, the sealing apparatus 80 may bean adhesive 82 that is applied to the second, inward-facing side 79 ofthe flap extension 77 to provide such a seal against the epidermis 16.The sealing apparatus 80 may be used to hold the sealing member 72against the patient's epidermis 16 or another layer, such as a gasket oradditional sealing member. The sealing apparatus 80 may take numerousforms. For example, the sealing apparatus 80 may be a medicallyacceptable, pressure-sensitive adhesive that extends about a peripheryof the sealing member 72.

The reduced-pressure subsystem 90 includes a reduced-pressure source 92,or therapy unit. The reduced-pressure source 92 provides reducedpressure. The reduced-pressure source 92 may be any device for supplyingreduced pressure, such as a vacuum pump, wall suction, or other source.While the amount and nature of reduced pressure applied to a tissue willtypically vary according to the application, reduced pressure willtypically be between −5 mm Hg and −500 mm Hg and more typically between−100 mm Hg and −300 mm Hg. In one embodiment, the reduced pressure isheld around −200 mm Hg. The reduced-pressure source 92, for convenienceand mobility purposes, may be a battery-operated unit that is capable ofproviding a continuous and intermittent reduced pressure. Thereduced-pressure source 92, or therapy unit, may include a canister 94,or reservoir, and may be provided with windows 96 to allow the patientor healthcare provider to view the fill status of the canister 94. Thereduced pressure subsystem 90 further includes a reduced-pressuredelivery conduit 98, or medical tubing, which if fluidly coupled to areduced-pressure interface 100, such as a port 102. The reduced-pressuredelivery conduit 98 and the reduced-pressure interface 100 allow reducedpressure to be delivered into the sealing subsystem 70.

As used herein, “reduced pressure” generally refers to a pressure lessthan the ambient pressure at a linear wound 12, tissue site, ortreatment site that is being subjected to treatment. In most cases, thisreduced pressure will be less than the atmospheric pressure at which thepatient is located. Alternatively, reduced pressure may be less than ahydrostatic pressure at the tissue site. Unless otherwise indicated,values of pressure stated herein are gauge pressures. Reduced pressuredelivered may be constant or varied (patterned or random) and may bedelivered continuously or intermittently. Although the terms “vacuum”and “negative pressure” may be used to describe the pressure applied tothe tissue site, the actual pressure applied to the tissue site may bemore than the pressure normally associated with a complete vacuum.Consistent with the use herein, an increase in reduced pressure orvacuum pressure typically refers to a relative reduction in absolutepressure.

The closing dressing bolster 46 may be made from a polymer and ispreferably a soft polymer. In one illustrative embodiment, the closingdressing bolster 46 is a material having a durometer of 50 Shore A, butother materials and characteristics are possible. The closing dressingbolster 46 and the bolster body 50 may be made of a see-throughmaterial, as is a sealing member 72, in order to allow the color, shadesof color, wound edges, or other features of the linear wound 12 to beviewed from a point external to the reduced-pressure system 10 (see FIG.6). A color change, or change in the shade of a color, of the linearwound 12 can signify the onset of infection or other issues, and suchvisual cues provide useful information to the healthcare provider. Thebolster body 50 may be made from a flexible closing bolster material,e.g., a soft polymer, a medical grade silicone, or other suitablematerial. The closing dressing bolster 46 may be extruded, pour molded,injection molded, blow molded, or formed by other manufacturingtechniques. “Flexible” means able to move enough to generate the inwardclosing force.

Referring now primarily to FIG. 2, the closing dressing bolster 46 isshown with a plurality of apertures 64 formed on a second, inward-facingside or surface 49 of a second wall 55, or bottom wall, of the bolsterbody 50. The apertures 64 are formed under a center portion 66, and inparticular, near center line 68 of the bolster body 50. A detail showingone aperture 64 is shown in FIG. 3C. A first wall 53, or top wall, andthe second wall 55 are coupled in a spaced relationship to form a hollowregion or central compartment 57. Referring again primarily to FIG. 2,the apertures 64 facilitate the transmission of reduced pressure by thebolster body 50 to the linear wound 12. Additional apertures in variouspatterns may be provided in the bolster body 50 to facilitatecommunication of reduced pressure to the patient's epidermis 16, and, inparticular, to the linear wound 12. One or more apertures, such asaperture 65, may be formed on a first side 47 of the first wall 53 ofthe bolster body 50. Closing members 52, 54, 56, 58, 60, and 62 areshown on the second, inward-facing side 49. Closing members 52, 56, and58 are on a first lateral side of the center portion 66 and closingmembers 54, 60, and 62 are on a second lateral side of the centerportion 66.

As shown clearly in FIGS. 3A and 3B, an oblique surface 69 has an angleformed with respect to an imaginary plane extending vertically (verticalfor the orientation shown in FIG. 2). The oblique surface 69, which isopposite a surface 63, is shown making an angle 61 with respect to areference vertical plane 59 formed at the apex of the oblique surface69.

In operation, when treatment is desired, the closing dressing bolster 46is placed over the linear wound 12 with the center portion 66 over thelinear wound 12 proximate a center wound area 45. If the closingdressing bolster 46 is not pre-manufactured with the sealing member 72applied on the first side 47, then the sealing member 72 is applied overthe first side 47 of the closing dressing bolster 46 and beyond theclosing dressing bolster 46 to form the flap extension or drapeextension 77. The drape extension 77 is either taped down or an adhesive82 is applied to provide a fluid seal between the sealing member 72 andthe patient's epidermis 16. “Fluid seal,” or “seal,” means a sealadequate to hold reduced pressure at the desired site given theparticular reduced-pressure subsystem involved.

The reduced-pressure subsystem 90 is fluidly coupled to the sealingsubsystem 70 through the reduced-pressure interface 100. Thereduced-pressure source 92 is activated and develops and deliversreduced pressure through the reduced-pressure delivery conduit 98 to thereduced-pressure interface 100. When activated, the reduced-pressuresource 92 delivers reduced pressure to the sealing subsystem 70 andreduced pressure causes the closing dressing bolster 46 to develop thecompressive force 42. The geometry of the closing dressing bolster 46may cause a bending moment to develop about the center portion 66 andthereby cause the closing members 52, 54, 56, 58, 60, and 62 to developa resultant force downward and inward (for the orientation shown). Thisaction produces the directed force, e.g., the compressive force 42 orthe closing force 44. These forces may be experienced at or near thelinear wound 12.

Referring primarily to FIG. 2, the development of the closing force orcompressive force is described in more detail. Each of the obliquesurfaces 69 between adjacent closing members, 58 and 56, 56 and 52, 52and 54, 54 and 60, and 60 and 62, form part of a triangle-shaped ridge,each having an apex: first apex 67, second apex 71, central apex 75,third apex 83, and fourth apex 85. As the reduced pressure enters theaperture 65, the central compartment 57 is evacuated until some or allof the apexes 67, 71, 75, 83, and 85 encounter the first wall 53.Reduced pressure is also delivered from the central compartment 57through apertures 64 and may provide a force urging the apexes higher,or trying to make the angle associated with each apex smaller. As aresult of one or more of these actions, the closing members 52, 54, 56,58, 60, and 62 are urged toward the center line 68 and, through frictionagainst the patient's epidermis from the closing members 52, 54, 56, 58,60, and 62, the closing force is developed on the patient's epidermis.The compressive force may be developed as the first wall 53 and secondwall 55 are pulled by reduced pressure toward the patient or in thedirection going from the first wall 53 to the second wall 55.

Referring now primarily to FIGS. 4A, 4B, 4C, and 4D, anotherillustrative embodiment of a closing dressing bolster 146 is presented.The closing dressing bolster 146 has a bolster body 150 formed with afirst closing member 152 and a second closing member 154. A thirdclosing member 156 and a fourth closing member 158 are also shown. Theclosing members 152 and 156 are formed on a first side or first portion153 which is one side of a center plane 168, or center portion, and mayextend the longitudinal length of the closing dressing bolster 146. Theclosing members 154 and 158 are formed on a second portion or side 155,which is on the other side of the center plane 168.

A central trough area 157 may help the bolster body 150 to flex in thatregion as a bending moment is developed under reduced pressure. Thebending moment helps to press the closing members 152, 154, 156, and 158into the patient's epidermis and may provide the directed force, e.g.,the compressive force and closing force directed towards the centralwound area (e.g., area 45 in FIG. 1). The shape of the bolster body 150in this illustrative embodiment has been chosen for strength and ease inextruding from a material, e.g., silicone, and so that the bolster body150 collapses or moves in a desired way to develop the directed force,e.g., the compressive or closing forces. The closing dressing bolster146 may be made of a see-through or at least partially transparentmaterial so that the closing dressing bolster 146 may help the color,shades of color, wound edge, or other features of the linear woundunderneath the closing dressing bolster 146 be viewed from a pointexterior to a system utilizing the closing dressing bolster 146.

As shown in FIGS. 4A and 4B, a tubing connector 199 may be used toprovide reduced pressure to the closing dressing bolster. The tubingconnector 199 is sized and configured to mate with central trough area157 on the closing dressing bolster 146. The tubing connector 199 isfluidly coupled to a reduced-pressure delivery conduit 198 wherebyreduced pressure is delivered to the closing dressing bolster 146.Apertures 151 allow reduced pressure to communicate inside the closingdressing bolster 146. As shown clearly in FIG. 4C, an aperture 164 maybe formed in a portion of the closing dressing bolster 146 to helpcommunicate reduced pressure to the linear wound below.

Referring now primarily to FIGS. 4C-4D, the development of the closingforce or a compressive force will be described in more detail. In thisillustrative embodiment, the bolster body 150 has been extruded with acentral compartment 123 and a plurality of compartments. Six of theplurality of compartments 111, 113, 115, 117, 119, and 121 are formed onthe first portion 153. The central compartment 123 is formedsubstantially adjacent to the central trough 157. Six of the pluralityof compartments 125, 127, 129, 131, 133, 135, and 137 are formed on thesecond portion 155. In this embodiment, only the central compartment 123receives reduced pressure and does so through apertures 151.

The plurality of compartments, e.g., compartments 111, 113, 115, 117,119, 121, 125, 127, 129, 131, 133, 135, and 137, are formed using afirst wall 139 (or top wall), a second wall 141 (or bottom wall), and aplurality of web members 143. The plurality of compartments providesstrength to keep the first wall 139 from collapsing against the secondwall 141, except that a lower portion 145 of the central trough 157 isdesigned to collapse under reduced pressure against a shelf portion 161of the central compartment 123. It should be noted that first closingmember 152 and second closing member 154 are spaced apart and sized andconfigured to provide a treatment trough 163. The treatment trough 163may have a dome-cutout 165 and oblique walls 167. The first closingmember 152 is formed on a first lateral portion with respect to thecenter plane 168, and the second closing member 154 is formed on asecond lateral portion with respect to the center plane 168.

As reduced pressure is delivered to apertures 151, the reduced pressureenters the central compartment 123 and is delivered through aperture 164into the treatment trough 163. The reduced pressure causes the lowerportion 145 of the central trough 157 to collapse and touch the shelfportion 161 of the central compartment 123. In addition, reducedpressure in the treatment trough 163 pulls the oblique walls 169 towardseach other. One or more of these actions causes the bolster body 150 toflex, or bend, about the center plane 168 and thereby urges the closingmembers towards the center plane 168. The plurality of compartmentspreferably do not collapse and continue to provide strength. Moreover,as the reduced pressure pulls the closing dressing bolster 146 inward,i.e., in the direction going from the first wall 139 to the second wall141, and a compressive force is developed.

Referring now primarily to FIG. 5, another embodiment of a closingdressing bolster 246 is presented. The closing dressing bolster 246includes a bolster body 250 formed with a first closing member 252 on afirst side 253, or first lateral side, and a second closing member 254on a second side 255, or second lateral side. The first and secondclosing members 252 and 254 have oblique walls that angle up (fororientation shown) toward the wicking material holder 236. With respectto a center portion 268, an overlay piece 265, or overlay, may cover andhold the closing members 252 and 254. A gap between closing members 252and 254 forms a wicking-material holder 236 that holds a wickingmaterial 238. The shape of the wicking material 238 and the substance ofthe wicking material 238 may be operable to help keep an underlyinglinear wound (e.g., linear wound 12 in FIG. 1) dry and clean.

The materials that may be used for the wicking material 238 includehydrophobic materials, hydrophilic materials, and all the materialslisted elsewhere that may be used for a shaped dressing bolster 532described below (see FIG. 8). The overlay piece 265 and closing members252 and 254 may be made of a see-through material that allows theclosing dressing bolster 246 to be used with a system that allows ahealthcare provider to view the color, shades of color, wound edges, orother features of the linear wound beneath the closing dressing bolster246 from a point external to the closing dressing bolster 246 (see FIG.6 for an example) and external to the system.

In operation, the closing dressing bolster 246 may develop a bendingmoment under reduced pressure causing the lower portion of the firstclosing member 252 and the lower portion of the second closing member254 to press downward (for the orientation shown) and inward on thepatient's epidermis causing both a compressive force or a closing forcetowards the linear wound. Reduced pressure delivered to thewicking-material holder 236 may move the first closing member 252 andthe second closing member 254 closer together and thereby provide theclosing force. The closing dressing bolster 246 is sized and configuredso that the wicking material 238 may be in contact with the linear woundand thereby helps to remove any fluids that might have emanated from thelinear wound. Any such fluids would be delivered to a reduced-pressureinterface and then be delivered by a reduced-pressure conduit to acanister under the influence of a reduced-pressure source.

The illustrative closing dressing bolsters 46, 146, and 246 presentedabove may provide for the visual determination of the color, shades ofcolor, wound edge, or other features of the wound from a locationexternal to the closing dressing bolster. This feature is also possiblewith other types of dressings as will now be discussed. Referring now toFIG. 6, a portion of a reduced-pressure treatment system 310 is shown.The reduced-pressure treatment system 310 includes a see-throughdressing assembly 340, which has a bolster body 350. The bolster body350 may be made of any number of materials, such as a bolster mesh orbolster foam, provided that the spacing of pores on the foam (non-opaquefoam) or between structural elements of the material allow forsufficient light to pass through the material such that the color,shades of color, wound edge, or other features of a linear wound 312 canbe seen from a point external to the reduced-pressure treatment system310, e.g., can be seen in a line of sight location shown by referencenumeral 384. For example, the bolster body 350 may be formed fromsilicone or porous foam, e.g., a GranuFoam® material available fromKinetic Concepts, Inc. of San Antonio, Tex. The pore size and densitymay be varied to help provide the see-through characteristic.

In an alternative illustrative embodiment, a window 386, such as awindow made of see-through silicone, may be placed over a portion of thebolster material such that when reduced pressure is provided to thebolster body 350 and the window 386 is compressed down further on thebolster material, the linear wound 312 becomes visible through thewindow 386 from a point exterior to the bolster body 350 and the system310. For example, a patient or healthcare provider may see the linearwound 312 on a line of sight 388.

In another alternative, illustrative embodiment, clear beads may be usedas or included within bolster body 350. The beads may be arranged withinthe bolster body so that under negative pressure, the beads cometogether over the wound allowing the patient or healthcare provider tosee through to the wound from a point exterior or external to thebolster body 350 and the system 310. The body bolster 350 may be a meshmaterial that the beads can displace as they come together under reducedpressure.

In another embodiment, a window can be made such that when reducedpressure is removed from the bolster body 350, a biased portion movesaside allowing one to view the linear wound 312. For example, twoportions of the bolster body 350 may overlap as reduced pressurecompresses the two portions, but when reduced pressure is removed, theportions separate and allow a clear view of the linear wound. As such,it will be appreciated that numerous visual inspection devices may beused to allow the color and other characteristics of the wound to bevisually detected. The visual inspection device may be a see-throughbolster and a see-through sealing member, a window 386, a bolstermaterial that allows adequate light to pass, a plurality of clear beads,or a moveable portion of a bolster that allows visual inspection whennot under reduced pressure.

The bolster body 350 is shown covered by a sealing member 372 thatextends beyond the bolster body 350, e.g., beyond edge 348, to form adrape extension 377. The drape extension 377 may be sealed to form afluid seal between the sealing member 372 and a patient's epidermis 314using a sealing apparatus 380, such as a drape tape 383 or other sealingdevice.

Referring now primarily to FIG. 7, a portion of an illustrative system410 for treating a linear wound 412 is presented. The system 410includes a dressing assembly 440. The dressing assembly 440 includes adressing bolster 446, which has a dressing body 450. The dressing body450 may be formed with two portions: the first side, or first lateralportion 453, and a second side, or second lateral portion 455. The firstportion 453 and second portion 455 may be integrally connected or may betwo separate pieces. The first portion 453 is formed with closingmembers 452 and 456. The second portion 455 is formed with closingmembers 454 and 460. Under reduced pressure, the closing members 452,454, 456, and 460 develop both a compressive force and a closing forcetowards the linear wound 412. The dressing body 450 is shown covered bya sealing member 472 that is sealed with a sealing apparatus 480 toprovide a seal against a patient's epidermis 416.

A first wall 437 on the first portion 453 and a second wall 439 on thesecond portion 455 together may form a wicking-material holder 436 forholding a wicking material 438. The wicking material 438 may be heldagainst the linear wound 412 to help to remove any fluids, e.g.,exudates, when the dressing assembly 440 is place under reducedpressure.

Referring now primarily to FIG. 8, an illustrative see-through woundtreatment system 510 is presented that allows a healthcare provider toview a treatment site, e.g., linear wound 512, area wound, a portion ofintact epidermis 514, etc., and may provide a compressive force. Thesee-through wound treatment system 510 may provide for the treatment ofsubcutaneous damaged tissue and may allow the treatment site to beviewed from a place external to the see-through wound treatment system510.

The see-through wound treatment system 510 is shown in a peri-incisionalregion around the linear wound 512, which is through the epidermis 514,dermis 516, and reaching into a hypodermis, or subcutaneous tissue 518.The subcutaneous tissue 518 may include numerous tissue types, such asfatty tissue or muscle. A damaged subcutaneous tissue site 520 is shownextending out from the linear wound 512 and includes, in this instance,a subcutaneous defect, dead space, or void 522. The damaged subcutaneoustissue site 520 may be caused by surgical procedures, such asliposuction. The damaged subcutaneous tissue site 520 may include voids,such as the void 522, open spaces, and various defects that can betroublesome for a number of reasons, such as fluid accumulation that mayresult in edema.

The linear wound 512 may be closed using any closing device ortechnique, such as staples, sutures, or adhesive, but is shown in thisillustrative embodiment with a staple 513. The see-through woundtreatment system 510 may be used for treating an area and, inparticular, may be used for treating a subcutaneous tissue site 520 andthe tissue around subcutaneous tissue site 520, but the see-throughwound treatment system 510 may also be used to treat the more limitedarea of a linear wound 512.

The see-through wound treatment system 510 includes a dressing assembly530, which includes the shaped dressing bolster 532, a sealing subsystem560, and a reduced-pressure subsystem 580. In operation, the see-throughwound treatment system 510 may develop the directed force, which mayinclude a net compressive force, represented by reference numerals 524,that is realized in the subcutaneous tissue site 520. As describedfurther below, the shaped dressing bolster 532 may be shaped andconfigured to allow the compressive force 524 to be distributed fairlyevenly over the patient's epidermis 514. Otherwise, if there are areasof substantially increased force as compared to other areas on theepidermis 514, skin irritation may result.

The directed force may also include the closing force, or inward force,i.e., a force towards an interior portion of the dressing assembly 530.The closing force is represented by reference numerals 526. The closingforce 526 remains substantially within the plane of the epidermis 514.In other words, the closing force 526 operates mainly within theepidermis 514. In addition, the see-through wound treatment system 510is operable to deliver reduced pressure to the linear wound 512 and,depending on the phase of healing and the nature of the linear wound512, through the linear wound 512 such that reduced pressure is realizedat the level of any subcutaneous voids 522 to help approximate—bringtogether—the tissues in that region as well as to help remove any air orany other fluids.

The dressing assembly 530 includes the shaped dressing bolster 532 thathas a first side 534 and a second, inward-facing side 536. The shapeddressing bolster 532 may be sized and shaped to substantially match theestimated area of the damaged subcutaneous tissue site 520 although alarger or smaller size may be used in different applications. The shapeddressing bolster 532 has an edge 538. The shaped dressing bolster 532may be made of a number of different medical bolster materials, i.e.,materials suitable for use in medical applications and that may be madesterile. In one illustrative embodiment, the shaped dressing bolster 532is made from a medical bolster material that is a manifold material. Inone illustrative embodiment, the shaped dressing bolster 532 is madefrom bolster material that is a porous and permeable foam-like materialand, more particularly, a reticulated, open-cell polyurethane orpolyether foam that allows good permeability of wound fluids while underreduced pressure. One such foam material that has been used is the VAC®GranuFoam® material available from Kinetic Concepts, Inc. (KCI) of SanAntonio, Tex. Any material or combination of materials may be used forthe bolster material provided that the bolster material is operable todistribute, or manifold, reduced pressure.

The term “manifold” as used herein generally refers to a substance orstructure that is provided to assist in applying reduced pressure to,delivering fluids to, or removing fluids from a tissue site. The bolstermaterial may also be a combination or layering of materials; forexample, a first bolster layer of hydrophilic foam may be disposedadjacent to a second bolster layer of hydrophobic foam to form thebolster material. The term “fluid” as used herein generally refers togas or liquid, but may also include any other flowable material,including but not limited to gels, colloids, and foams.

The reticulated pores of the Granufoam® material, which are typically inthe range of about 400 to 600 microns, are helpful in carrying out themanifold function, but other materials may be used. The density of themedical bolster material, e.g., Granufoam® material, is typically in therange of about 1.3 lb/ft³-1.6 lb/ft³ (20.8 kg/m³-25.6 kg/m³). A materialwith a higher density (smaller pore size) than Granufoam® material maybe desirable in some situations. For example, the Granufoam® material orsimilar material with a density greater than 1.6 lb/ft³ (25.6 kg/m³) maybe used. As another example, the Granufoam® material or similar materialwith a density greater than 2.0 lb/ft³ (32 kg/m³) or 5.0 lb/ft³ (80.1kg/m³) or even more may be used. The more dense the material is, thehigher compressive force that may be generated for a given reducedpressure. If a foam with a density less than the tissue at the tissuesite is used as the medical bolster material, a lifting force may bedeveloped.

The bolster material may be a reticulated foam that is later felted tothickness of about ⅓ the foam's original thickness. Among the manypossible materials, the following may be used: GranuFoam® material or aFoamex® technical foam (www.foamex.com). In some instances it may bedesirable to add ionic silver to the bolster material in a microbondingprocess or to add other substances to the bolster material, such asantimicrobial agents. The bolster material may be isotropic oranisotropic depending on the exact orientation of the directed forcethat is desired during reduced pressure. The bolster material may bemade anisotropic by adding filaments, felting a portion, adding adhesiveselectively, etc. The bolster material could be a bio-absorbablematerial.

The sealing subsystem 560 includes a sealing member 562, or drape, whichis analogous to the sealing member 72. The sealing member 562 may becoupled to the shaped dressing bolster 532. For example, the sealingmember 562 and shaped dressing bolster 532 may be coupled usingadhesives, such as an acrylic adhesive, silicone adhesive, hydrogel,hydrocolloid, etc. As another example, the sealing member 562 and theshaped dressing bolster 532 may be bonded by heat bonding, ultrasonicbonding, and radio frequency bonding, etc. The coupling may occur inpatterns or completely. Structure may be added to the bond to make thesealing member 562 behave anisotropically in a desired direction, i.e.,to make an anisotropic drape material. An anisotropic drape materialhelps the dressing assembly 530 to primarily move in a given direction,i.e., only about a certain axis or axes.

In the illustrative embodiment of FIG. 8, the sealing member 562 may besized to extend beyond the shaped dressing bolster 532, e.g., beyond theedge 538 on an extremity 533, to form a drape extension 564, orextension. The drape extension 564 has a first surface 566 and a second,inward-facing surface 568. The sealing member 562 may be sealed againstthe epidermis 514 of the patient using a sealing apparatus 569, whichhelps to provide a seal and allows reduced pressure to be maintained bythe reduced-pressure subsystem 580 at the treatment site. The sealingapparatus 569 may take numerous forms, such as an adhesive 570; asealing tape, or drape tape or strip; double-side drape tape; paste;hydrocolloid; hydrogel; or other sealing device. If a tape is used, thetape may be formed of the same material as the sealing member 562 with apre-applied, pressure-sensitive adhesive. The pressure sensitiveadhesive 570 may be applied on the second, inward-facing surface 568 ofthe drape extension 564. The pressure-sensitive adhesive 570 provides aseal between the sealing member 562 and the epidermis 514 of thepatient. Before the sealing member 562 is secured to the patient, thepressure-sensitive adhesive 570 may have removable strips or backingcovering the pressure-sensitive adhesive 570.

The reduced-pressure subsystem 580 includes a reduced-pressure source582, or therapy unit, which can take many different forms. Thereduced-pressure source 582 provides reduced pressure as a part of thesee-through wound treatment system 510. The reduced-pressure source 582may be any device for supplying reduced pressure, such as a vacuum pump,wall suction, or other source. While the amount and nature of reducedpressure applied to a tissue will typically vary according to theapplication, reduced pressure will typically be between −5 mm Hg and−500 mm Hg and more typically between −100 mm Hg and −300 mm Hg. Inorder to maximize patient mobility and ease, the reduced-pressure source582 may be a battery-powered, single-use reduced-pressure generator,which facilitates application in the operating room and providesmobility and convenience for the patient during the rehabilitationphase.

In the illustrative embodiment of FIG. 8, the reduced-pressure source582 is shown having a battery compartment 584 and a canister region 586with windows 588 providing a visual indication of the level of fluidwithin the canister region 586. An interposed membrane filter, such ashydrophobic or oleophobic filter, may be interspersed between areduced-pressure delivery conduit, or tubing, 590 and thereduced-pressure source 582.

Reduced pressure developed by reduced-pressure source 582 is deliveredthrough the reduced-pressure delivery conduit 590 to a reduced-pressureinterface 592, which may be an elbow port 594. In one illustrativeembodiment, the elbow port 594 is a TRAC® technology port available fromKCI of San Antonio, Tex. The reduced-pressure interface 592 allowsreduced pressure to be delivered to the sealing subsystem 560 andrealized within an interior portion of the sealing subsystem 560. Inthis illustrative embodiment, the elbow port 594 extends through thesealing member 562 and into the shaped dressing bolster 532.

In operation, the see-through wound treatment system 510 is applied tothe linear wound 512. The see-through wound treatment system 510 may beapplied to the linear wound 512 in the operating room after a surgicalprocedure on the patient. The second, inward-facing side 536 of theshaped dressing bolster 532 is placed against the patient's epidermis514 with the shaped dressing bolster 532 over the damaged subcutaneoustissue site 520 and with a portion of the shaped dressing bolster 532over the linear wound 512. The dressing assembly 530 may be sized forthe typical application involved in the procedure performed by ahealthcare provider. The dressing assembly 530 may be sized, shaped, andconfigured to work with different anatomical applications, such as theabdomen, chest, arms, thighs, etc.

If the sealing member 562 has not already been coupled, the sealingmember 562 is placed over the first side 534 of the shaped dressingbolster 532 with a portion extending beyond the shaped dressing bolster532 to form the drape extensions 564. The drape extensions 564 may thenbe taped down or an adhesive 570 used to form a seal between the sealingmember 562 and the patient's epidermis 514. The seal need only beadequate to allow the see-through wound treatment system 510 to holdreduced pressure on the desired treatment area. The reduced-pressureinterface 592 and the reduced-pressure source 582 are fluidly coupledusing the reduced-pressure delivery conduit 590. The reduced-pressuresource 582 may then be activated and reduced pressure delivered to theshaped dressing bolster 532.

As the pressure is reduced in the shaped dressing bolster 532, theshaped dressing bolster 532 compresses and contracts laterally and formsa semi-rigid substrate, and a number of beneficial forces and actionsmay take place. Reduced pressure is transmitted further still throughthe shaped dressing bolster 532 so that reduced pressure delivered tothe linear wound 512. At least at the early stages of the healingprocess, reduced pressure may also be realized through the linear wound512 and into the subcutaneous tissue site 520. As such, reduced pressuremay help close defects, such as subcutaneous void 522, and generallyprovides stability to the area. Reduced pressure delivered to the shapeddressing bolster 532 also develops the compressive force 524 that againmay provide stability and therapy. The compressive force 524 is morethan just at the top of the epidermis 514. The compressive force 524extends down deeper and may be experienced at the level of thesubcutaneous tissue site 520. The compressive force may help closedefects and provide stability.

It may be desirable to apply the see-through wound treatment system 510in the operating room and allow the see-through wound treatment system510 to remain on the patient until adequate healing has taken place. Inthis regard, it may be desirable to form the sealing member 562, shapeddressing bolster 532, and any other layers from see-through materialsthat allow the healthcare provider to gain visual cues about the healingof the linear wound 512 and damaged subcutaneous tissue site 520 withouthaving to remove the dressing assembly 530.

According to one illustrative embodiment, a see-through dressingassembly for use with a reduced-pressure system for treating a linearwound on a patient includes a closing dressing bolster for providing aclosing force when under reduced pressure and a sealing member forcovering the closing dressing bolster and providing a seal over theclosing dressing bolster. The closing dressing bolster and sealingmember are formed from see-through materials sufficient to allowperception of color from a point external to the see-through dressingassembly. The closing dressing bolster may include a top wall and abottom wall. The top wall and bottom wall are coupled in a spacedrelationship. The bottom wall includes a center portion, a first lateralportion, and a second lateral portion. A first closing member is formedon the first lateral portion, and a second closing member is formed onthe second lateral portion. When placed under reduced pressure, thefirst closing member and the second closing member move towards eachother.

According to one illustrative embodiment, a system for treating a woundon a patient with reduced pressure and that allows visual observation ofthe wound during treatment includes a dressing bolster for placing on aportion of the patient's epidermis over the wound. The dressing bolsteris formed from a see-through material. The system further includes asealing subsystem for providing a seal over the closing bolster and thepatient's epidermis and a reduced-pressure subsystem for delivering areduced pressure to the sealing subsystem. The sealing subsystem andreduced-pressure subsystem are operable to deliver reduced pressure tothe dressing bolster. The dressing bolster, sealing subsystem, andreduced-pressure subsystem are operable to develop a directed force andto deliver reduced pressure to the wound. The sealing subsystem includesa see-through sealing member. The dressing bolster and sealing subsystemare operable to allow light to pass such that shades of color of thewound may be perceived from a place external to the system. The dressingbolster has a first surface, a second, inward-facing surface andincludes an oblique extremity formed a portion of the dressing bolster.The dressing bolster is formed from a medical bolster material that hasa density greater than 20 kg/m3. The dressing bolster has thecharacteristic of evenly distributing a directed force when under areduced pressure.

Although the subject matter of the present disclosure has been describedin the context of certain non-limiting embodiments, various changes,substitutions, permutations, and alterations can be made withoutdeparting from the scope of the disclosed subject matter as defined bythe appended claims. Any feature described in a connection to any oneembodiment may also be applicable to any other embodiment.

We claim:
 1. A closing dressing bolster for treating a linear wound,comprising: a bolster body formed from a flexible closing bolstermaterial and having a center portion; the bolster body comprising: a topwall and a bottom wall, the top wall and the bottom wall coupled in aspaced relationship to form a hollow region, the bottom wall having afirst lateral portion on one side of the center portion, and a secondlateral portion on another side of the center portion, a first closingmember formed on the first lateral portion, and a second closing memberformed on the second lateral portion; wherein the first closing memberand the second closing member define therebetween, a treatment troughhaving oblique walls.
 2. The closing dressing bolster of claim 1,wherein the bolster body is formed from a see-through material.
 3. Theclosing dressing bolster of claim 1, wherein the bolster body is formedfrom silicone.
 4. The closing dressing bolster of claim 1, wherein thebolster body further comprises a wicking-material holder, and whereinthe closing dressing bolster further comprises a wicking materialassociated with the wicking-material holder.
 5. A closing dressingbolster for treating a linear wound, comprising: a bolster body formedfrom a flexible closing bolster material; the bolster body comprising: afirst closing member formed on a bottom wall of the bolster body andhaving a first oblique wall, a second closing member formed on thebottom wall of the bolster body and having a second oblique wall, awicking-material holder formed by a gap between the first closing memberand second closing member, a wicking material disposed within thewicking-material holder, the wicking material having a fluid flowpathway for removing fluids; and wherein the first closing member andsecond closing member are operable, when the closing dressing bolster isunder reduced pressure, to move towards one another to develop an inwardforce.
 6. The closing dressing bolster of claim 5, wherein the firstclosing member and second closing member are operable, when the closingdressing bolster is under reduced pressure, to develop a compressionforce.
 7. The closing dressing bolster of claim 5, wherein the bolsterbody is formed from a see-through material.
 8. The closing dressingbolster of claim 5, wherein the bolster body is formed from silicone. 9.The closing dressing bolster of claim 5, wherein the first closingmember is formed on a first lateral side of a center portion of thebolster body and the second closing member is formed on a second lateralside of the center portion, and wherein the bolster body is operable todevelop a bending moment about the center portion when the closingdressing bolster is placed under reduced pressure.
 10. A closingdressing bolster for treating a linear wound, comprising: a bolster bodyformed from a flexible closing bolster material; a first closing memberformed on a tissue-facing surface of the bolster body, the first closingmember formed on a first lateral side of a center area and comprising afirst compartment; a second closing member formed on the tissue-facingsurface of the bolster body, the second closing member formed on asecond lateral side of the center area and comprising a secondcompartment; a wicking material holder formed by a gap between the firstclosing member and the second closing member and a wicking materialassociated with the wicking material holder: wherein the first closingmember and second closing member are operable to move towards each otherwhen placed under reduced pressure; wherein the bolster body is operableto develop a bending moment about the center area when the closingdressing bolster is placed under reduced pressure; and wherein thebolster body is operable to allow light to pass through sufficientlythat color may be detected from a location external to the closingdressing bolster.
 11. The closing dressing bolster of claim 10, whereinthe bolster body is formed from silicone.
 12. A method of manufacturinga closing dressing bolster for treating a linear wound, comprising:forming a bolster body from a flexible closing bolster material; whereinforming the bolster body comprises forming the bolster body with a firstlateral side and a second lateral side, and wherein bolster bodyincludes a central area, and wherein the first lateral side is on oneside of the central area and the second lateral side on another side ofthe central area; and wherein forming the bolster body furthercomprises: forming a first closing member on the bolster body on thefirst lateral side of the central area, forming a second closing memberon the bolster body on the second lateral side of the central area,forming the bolster body to develop a compressive force when placedunder reduced pressure, forming a gap between the first closing memberand the second closing member to provide a wicking material holder,wherein the bolster body is operable to develop a bending moment aboutthe central area when the closing dressing bolster is placed underreduced pressure, and wherein the first closing member and secondclosing member develop an inward closing force when the closing dressingbolster is placed under reduced pressure.
 13. The method of claim 12,wherein forming the bolster body further comprises forming the bolsterbody from a see-through material.
 14. The method of claim 12, whereinforming the bolster body further comprises forming the bolster body fromsilicone.
 15. The method of claim 12, wherein forming the bolster bodyfurther comprises providing a wicking material associated with thewicking material-holder.